Bavli, Shabas 10 amud 2, has (in my own translation):
And Rava b. Machseya said R. Chama b. Guria said Rav said, "One who gives a gift to his friend must inform him.…"
… Raban Shim'on b. Gamliel said, "One who gives bread to a child must inform his mother." What should he do to him? Abaye said, "Spread oil on him and apply eyeshadow to him."
Rashi explains that the oil and eyeshadow are "so his mother will ask him 'who did this?' and the child will tell her 'so-and-so did it, and he also gave me bread'".
Rashi explains, too, why this rule exists altogether, why we must inform our recipients:
must inform him: "I'll give you such-and-such gift". This is a honorable way: for he may be embarrassed to accept it, but because of the [advance warning] he will be appeased by words and not embarrassed about the matter. Similarly, if it were given in his home without his knowledge, one must inform him that it came to him by his hand, because then he will be his friend [literally: lover].
Only the second of those reasons applies to someone who's given bread to a child. So one is dabbing oil on the child in order that his mother will be the giver's friend; note that the giver of the bread is identified as male throughout (by use of masculine verbs, etc.). How do we explain this g'mara in light of the idea that a man should not be trying to make friends with another's wife? (Most mothers of children are married.)
 Citation needed.